Table Reflection Method (5.17)
The Table Reflection Method furnishes a fast and relatively accurate estimate of pavilion depth. In the diamonds that you get the chance to examine, you will see a reflection outline of the table onto the lower portion of the pavilion, when looking through the crown. The size of this reflection indicates the depth of the pavilion in question. For the ideal 43% depth, the reflection covers about 1/3 of the distance between the culet and the edge of the table where the stars join. If the reflection reaches one half of the distance, the depth is approximately 44.5% (too deep). As the reflection gets smaller the depth becomes shallower, and with a greater depth, the reflection becomes larger. It’s easy to remember larger is deeper, smaller is shallower. Again the ideal marker is the 43% depth (40.75°) with the reflection extending 1/3 of the way between the culet accurate and simple method.
When looking for this reflection, make sure the culet is centered under the table by holding the stone parallel to your loupe. The image of the octagon-shaped table itself consisting of eight surrounding star facets, is the landmark you will search for when identifying the reflection. These eight star reflections will probably be slightly distorted, but the distance from the culet will still be easy to estimate by eye. With very shallow pavilion depths, the reflection will be more difficult to distinguish due to its smaller size and lack of clear geometric shape. You will see the reflection, but it will not be as clear as say, in the 42 or 43% depth stones.
